[jeremyrockjock]

Hello, I have had this THC300 going on 4 years now and still have not got it working. I cannot seem to find and support for it. My first question in the setup is this line i copied and pasted from the setup manual that confuses the heck out of me.

With Mach3 running click on the Reset (solid Green) button on the lower left corner of the main screen. The Ready LED will light. And the set volts will be on the meter.
Adjust the set voltage to about 87volts.
Click on the “Torch ON” button the Mach3 screen. You will hear a relay click on the sensor board and see the Torch On LED light up on the Front Panel.
Center the coarse and fine controls (pointers UP).
The meter will drop to zero volts. This would normally read the actual tip volts at this time.


What Meter are they talking about? And how do you set it to 87 volts? I have been ruining tips too often because I cannot get this thing set right. Please help!!! Am I SOL on an outdated system?

[GaryCorlew]

I don't have one of these or a plazma table but have you been here and downloaded and read the docs THCDoc
Have you tried to contact Bob Campbell Campbell Designs - CNC with Bob Campbell

[jeremyrockjock]

Thanks Gary. The help links as where I copied the paragraph from.They don't clarify what the"meter" is that they are referring to. A few years ago I Spoke with Jim Cullins on the phone but last I has heard he was not doing well and was not doing support for the THC300. The webpage has not been updated since 2005. I hate to give up and needlessly spend money on another torch height controller.

[jeremyrockjock]

I'll try the Bob Campbell email.

[Torchhead]

Jim sold Sound Logic to Texas Microcircuits out of Texas. He sold the THC300 up until late last year. The THC 300 is a design based on a simple analog "knob chaser " I built for my first plasma table in 2001. I was the guy that had Art put the THC logic into he core of MACH. The meter on the THC300 just reads the Torch Volts while it is cutting so you have some form of feedback . In simple terms arc volts = arc gap. If you can see the arc volts and you know the type material and plasma settings it reflects the arc gap (height of the nozzle above the material) With the THC300 You just start a cut (at the right height) and "chase " the right height by setting first the course and then the fine knobs. Your indicated Torch Volts then should be close to what the cut chart for you plasma calls for There is more to it than that but I am pretty sure the THC300 manual is still up on the Texas Microcircuits website. There are a lot of other things that go with THC control to make it work. While the THC300 is better than no THC and even equal to or better than some of the ones you see today but there have been vast improvements in features and automation in the last few years.

TOMcaudle
www.Candcnc.com